Shockproof relay



y 5, 1958 E. M. VALEHRACH 2,833,882-

' SHOCKPROOF RELAY Filed Aug. '30, 1955 FIGJ.

INVENTOR. EMIL MVALEHRACH BY C ' ATTORNEY United States Patent 2,833,882 suoournoor RELAY Emil M. Valehrach, Wappingers Falls, N. Y., assignor to International Business Machines Corporation, New York, N. Y., a corporation of New York Application August 30, 1955,, Serial No. 531,514

4 Claims. (Cl. 200-87) This invention relates to electromagnetic devices and more particularly to electromagnetic relay and switching devices.

Electromagnetic relay and switching devices used in locations where they would be subjected to vibration and shock frequently fail in the performance of their designated functions. Such devices, if designed to be held closed, will inadvertently open or, if designed to be held open, will close due to the effect of shock or vibration upon the movable elements in the device.

Therefore, it is an object of this invention to provide an electrically operated relay or switching device which will not fail when it is subjected to the most severe conditions of shock or vibration.

Another object of this invention is to provide an electrically operated relay or switching device, the construction of which provides for a device wherein the flux losses are a minimum and the forces of the same are a maximum.

A further object of this invention is to provide an electrically operated relay or switchingdevice which is rapid in response to energization current.

Another object of this invention is to provide an electrically operated relay or switching device which is so constructed that it operates equally Well in any position.

Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principle of the invention and the best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. l is a plan view of the improved switching device with parts broken away to facilitate illustration.

Fig. 2 is a sectional view taken on line 22 in Fig. 1.

Referring to the drawings it Will be noted that the improved switching device, generally designated 1, is in the form of a torrid but it must be appreciated that the invention may assume other physical configurations without deviating from the spirit of the present invention.

The switching device comprises a pair of annular members 2 and 3 which are of a semi-circular shape in cross section, as shown in Fig. 2. The fiat faces of the members are cut away so as to provide an annular space t when the members are arranged one upon the other as shown. It will be noted that the space 4 on planes extending radially of the member 1 is bounded by surfaces 59 and 6 which flair outwardly from an inner surface '7. Any suitable insulating material, such as plastic or hard rubber, may be used in making the mebers 2 and 3.

Arranged within the space 4 are arcuate contact segments 10, 11, 12, and 13 made of a magnetic material. Each of these segments in cross section has substantially the same shape as the space and fits snugly within this space. The ends of the segments 10 and 13 adjacent to each other are separated by insulating material 14 which may, for example, be plastic formed integral with the Patented May 6, 1958 plastic members 2, 3, and project from the latter into the space 4. The other ends of the segments 10, 13 and both ends of the segments 11 and 12 are provided with projecting portions 15 at their inner edges. The remainder of each segment end is bounded by a plane surface 16 extending radially of the members 2 and 3. it will be noted that the surfaces 16 on adjacent ends of the segments cooperate with each other and with the surfaces and 6 to form a pocket 18 which increases in cross sectional area in proportion to the radial distance from the center of the members 2 and 3.

Arranged within each pocket 18 is a ball shaped con tact element 19 made of magnetic material and engageable with the projecting portions 15 on the segments to conmeet the latter electrically with each other. Regardiess of the position in which the switching device is placed one or more of the contact elements 19 will tend to move outwardly from the projecting portions 15 by the for of gravity. When the switching device is in a horizontal plane, the contact elements will all tend to roll outwardly on either surface 5 or 6. When arranged in a vertical plane, at leastone of the contact elements will tend to roll outwardly on one of the surfaces 16.

In order to prevent the contact segments from moving longitudinally relative to each other there are provided plastic portions 20 formed integral with the members 3 and projecting into the space between the portions 15 on the contact segments. Care must be taken to make the portions 20 of such dimensions that they do not interfere with the seating of the contact elements. Fixed to the contact segments 14 and 13 near their adjacent ends are terminals 22 and 23 which project outwardly through openings between the members 2 and 3.

The structure so far described is assembled by placing the contact segments in their proper positions between the projecting plastic portions on either the member 2 or 3. The contact elements 19 are then placed in the member between the surfaces 16 on the contact segments and the other annular member is placed on the first. An insulating material 24, such as rubber or friction tape, is wrapped about the members 2 and 3 for holdig them to gether. Turns of wire 25 are then made about the taped members as shown, and the ends 26, 27 of the wire extend outwardly for connection to a suitable energizing means.

In operation, the terminals 22 and .23 are connected in a circuit which is to be closed in response to an energizing of the wire turns 25. With the turns deenergizcd, at least one of the contact elements 19 moves outwardly under the force of gravity and breaks the circuit through the contact segments. When the turns are energized, the lines of force produced cause the contact elements to move inwardly into engagement with the projecting portions 15 and complete the circuit from the terminal through the contact segments and the contact elements 19 to the terminal 23.

Upon deenergizing the wire turns 25, a residual magnetism exists and tends to hold the contact elements i in engagement with the projecting portions 15. To prevent this, a thin layer of silver is plated on the contact elements so that the reluctance to the lines of force at the points of contact between the contact elements and the portions 15 is sufficiently great to assure movement of the contact elements away from the projecting portions when the wire turns are deenergized. The contact elements may, if desired, be plated with any non-magnetic metal other than silver. It is only necessary that the metal used be a good conductor of electricity. The nonmagnetic metal could be plated, if desired, on the end of the contact segments instead of the contact elements.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a preferred embodiment, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. It is the intention therefore, to be limited only as indicated by the scope of the following claims.

What is claimed is:

l. A switching device comprising in combination, an annular casing of insulating material, contact segments arranged in said casing and spaced from each other, terminals connected to the adjacent ends of two of said segments and projecting outwardly through said casing, the other ends of said segments having plane surfaces extending radially of said casing and cooperating with each other and said casing to form outwardly flared pockets, ball shaped contact elements arranged in said pockets and engageable with the adjacent ends of said contact segments when moved inwardly within said pockets, and wire turns wrapped about said annular casing for producing, when electrically energized, a magnetic force to move said ball elements inwardly within said pockets.

2. A switching device comprising, in combination, an annular casing of insulating material, contact segments arranged in said casing and spaced from each other, portions on said casing projecting into the spaces between said segments for holding the latter against longitudinal movement relative to each other, terminals connected to the adjacent ends of two of said segments and projecting 4 with said projecting portions of said segments when moved to the inner ends of said pockets and wire turns wrapped about said annular casing.

3. The switching device of claim 2 in which there are four contact segments cooperating with each other and said casing to form three pockets spaced or more from each other.

4. A switching device comprising, in combination, a pair of annular plastic membersrecessed at one side and cooperating with each other to form a casing, contact segments ot magnetic material arranged in said casing and spaced from each other, portions on said annular members projecting inwardly between said segments for holding the latter against longitudinal movement relative to each other, terminals connected to the adjacent ends of two of said segments and projecting outwardly through said casing, the other ends of said segments having plane surfaces extending radially of said casing and cooperating with each other and said casing to form outwardly flared pocket, ball shaped contact elements of: magnetic material arranged in said pockets and engageable with the adjacent ends of said contact segments when moved inwardly within said pockets, a coating of nonmagnetic material on said contact elements, and wire turns wrapped about said casing.

References Cited in the file of this patent UNITED STATES PATENTS 685,549 Wurts Oct. 29, 1901 846,624 Saunders Mar. 12, 1907 2,715,166 Fitch Aug. 9, 1955 2,715,663 Bowes Aug. 16, 1955 2,744,976 Black May 8, 1956 FOREIGN PATENTS 428,146 France June 14, 1911 

